Rails type_for_column no longer takes a connection.

https://github.com/basecamp/activerecord-tenanted/blob/1e92cb34d0b7b02875040826330c1918abb06e9d/lib/active_record/tenanted/patches.rb#L38

Here we are setting a nil_connection but now rails no longer accepts a connection.
This will break the upgrade path.

```
ArgumentError: wrong number of arguments (given 2, expected 1)
/Users/lluarte/.local/share/mise/installs/ruby/3.4.7/lib/ruby/gems/3.4.0/bundler/gems/rails-76fcc3a31daf/activerecord/lib/active_record/attributes.rb:311:in 'type_for_column'
/Users/lluarte/.local/share/mise/installs/ruby/3.4.7/lib/ruby/gems/3.4.0/bundler/gems/activerecord-tenanted-855379f55d79/lib/active_record/tenanted/patches.rb:38:in 'block in ActiveRecord::Tenanted::Patches::Attributes::ClassMethods#_default_attributes'
```

Start at lib/active_record/tenanted/patches.rb#L38 and compare its type_for_column call with the Rails ActiveRecord code at attributes.rb:311 shown in the stack trace. Reproduce the ArgumentError on the upgrade path, then verify that the compatibility behavior works with Rails' current signature and that the error no longer occurs.

Written by the indexing model from the issue text.